<?php

namespace think\db\builder;

use think\db\Builder;

/**
 * Sqlsrv数据库驱动
 */
class Sqlsrv extends Builder
{
  protected $selectSql       = 'SELECT T1.* FROM (SELECT thinkphp.*, ROW_NUMBER() OVER (%ORDER%) AS ROW_NUMBER FROM (SELECT %DISTINCT% %FIELD% FROM %TABLE%%JOIN%%WHERE%%GROUP%%HAVING%) AS thinkphp) AS T1 %LIMIT%%COMMENT%';
  protected $selectInsertSql = 'SELECT %DISTINCT% %FIELD% FROM %TABLE%%JOIN%%WHERE%%GROUP%%HAVING%';
  protected $updateSql       = 'UPDATE %TABLE% SET %SET% FROM %TABLE% %JOIN% %WHERE% %LIMIT% %LOCK%%COMMENT%';
  protected $deleteSql       = 'DELETE FROM %TABLE% %USING% %JOIN% %WHERE% %LIMIT% %LOCK%%COMMENT%';

  /**
   * order分析
   * @access protected
   * @param mixed $order
   * @param array $options
   * @return string
   */
  protected function parseOrder($order, $options = [])
  {
    if (is_array($order)) {
      $array = [];
      foreach ($order as $key => $val) {
        if (is_numeric($key)) {
          if (false === strpos($val, '(')) {
            $array[] = $this->parseKey($val, $options);
          } elseif ('[rand]' == $val) {
            $array[] = $this->parseRand();
          }
        } else {
          $sort    = in_array(strtolower(trim($val)), ['asc', 'desc']) ? ' ' . $val : '';
          $array[] = $this->parseKey($key, $options) . ' ' . $sort;
        }
      }
      $order = implode(',', $array);
    }
    return !empty($order) ? ' ORDER BY ' . $order : ' ORDER BY rand()';
  }

  /**
   * 随机排序
   * @access protected
   * @return string
   */
  protected function parseRand()
  {
    return 'rand()';
  }

  /**
   * 字段和表名处理
   * @access protected
   * @param string $key
   * @param array  $options
   * @return string
   */
  protected function parseKey($key, $options = [])
  {
    $key = trim($key);
    if (strpos($key, '.') && !preg_match('/[,\'\"\(\)\[\s]/', $key)) {
      list($table, $key) = explode('.', $key, 2);
      if (isset($options['alias'][$table])) {
        $table = $options['alias'][$table];
      }
    }
    if (!is_numeric($key) && !preg_match('/[,\'\"\*\(\)\[.\s]/', $key)) {
      $key = '[' . $key . ']';
    }
    if (isset($table)) {
      $key = '[' . $table . '].' . $key;
    }
    return $key;
  }

  /**
   * limit
   * @access protected
   * @param mixed $limit
   * @return string
   */
  protected function parseLimit($limit)
  {
    if (empty($limit)) {
      return '';
    }

    $limit = explode(',', $limit);
    if (count($limit) > 1) {
      $limitStr = '(T1.ROW_NUMBER BETWEEN ' . $limit[0] . ' + 1 AND ' . $limit[0] . ' + ' . $limit[1] . ')';
    } else {
      $limitStr = '(T1.ROW_NUMBER BETWEEN 1 AND ' . $limit[0] . ")";
    }
    return 'WHERE ' . $limitStr;
  }

  public function selectInsert($fields, $table, $options)
  {
    $this->selectSql = $this->selectInsertSql;
    return parent::selectInsert($fields, $table, $options);
  }
}
